I would like someone to invent a device which does the exact opposite of an absorbtion heat pump.

For those who don't know what one is, an absorbtion heat pump is a gadget with three heat exchangers, at high, medium, and low temps; the high and low temp exchangers are heat sources for the device,
and the medium temp heat exchanger is the device's heat sink. As heat moves through an absorbtion heat pump from the high temp heat exchanger to the medium temp heat exchanger, it causes internal chemical reactions which then force heat to move from the low temp heat exchanger to the medium temp heat exchanger.

The (not yet invented) device I'm thinking of would have a medium temp heat exchanger as its heat source, and high and low temp heat exchangers as its heat sinks. So as heat flowed from the medium to the low temp exchanger, it would cause chemical reactions which would force heat to move from the medium temp heat exchanger to the high temp heat exchanger.

Such a device, if it could be built, would turn a low grade heat source and some form of heat sink into a high grade heat source.

As an example use, one could use solar thermal power (*without* reflectors or lenses to concentrate the sunlight beforehand) as the medium temp heat source, a geothermal loop (or possibly a cooling tower) as the heat sink, and anything requiring high temperatures as the high temperature heat sink -- such as the inside of an oven.

From a themodynamic standpoint, it's certainly possible -- it could easily be done using a mechanical heat engine coupled to a mechanical heat pump. But I'd like to see a more elegant, chemical solution, requiring little or no mechanical energy input, and few or zero moving parts.

So what you're basically saying is that you'd like to use domestic solar thermal collectors to cook on, but without concentrators. You'd use the energy gleaned from the [solar fluid to atmosphere heat engine] to provide power to a [solar fluid to oven/boiler heat pump]. It's doable with a pair of sterling engines strapped together, but a horrendously inefficient way of doing things from my point of view.

I guess the chemical systems you're referring to are 'latent heat of solution' based solar powered air conditioning units. I guess you'd have to sit down with a chemistry data book for a decade or so and pick out your working fluids.